The constellation Cassiopeia

Cassiopeia
Cassiopeia · Brightest star: SchedarShow constellation in the star registry

Fact sheet

Latin name
Cassiopeia (Cas)
Brightest star
Schedar (α Cas)
Relative brightness
2.24 mag
Hipparcos catalogue
HIP 3179
Area
598 deg² (rank: 25 out of 88)
Right ascension
22h 57m 05s to 3h 41m 14s
Declination
+46° 40' 33'' to +77° 41' 32''
Neighbouring constellations
Cepheus, Lacerta, Andromeda, Perseus, Camelopardalis

Visibility

Northern skyBerlin
Southern skySydney
visiblepartly visiblenot visible10 pm local time, on at least one day of the month

The constellation Cassiopeia

The constellation Cassiopeia is a constellation of the northern hemisphere. It is circumpolar around the North Pole. This means that its stars are so close to the celestial pole that they never set as seen from Berlin. The constellation is therefore above the horizon all year round there.

The brightest star of the constellation is α Cassiopeiae, which bears the Arabic name Schedar (breast). The five brightest stars together form an irregular W. After the seven stars of the Big Dipper, it is the second most striking star pattern in the northern sky. Cassiopeia and the Big Dipper are excellent for finding your way in the night sky, because Polaris (the Pole Star) lies between them. Polaris has a very special role. Because it lies almost exactly above the geographic North Pole, it is the only star in the northern hemisphere that always stays in the same place in the sky.

Mythology

According to Greek mythology, Cepheus was the king of Ethiopia. He was a descendant of the nymph Io, who was a lover of Zeus. Cepheus was married to the vain Cassiopeia, who boasted everywhere that she was even more beautiful than the Nereids, the fifty daughters of the sea god Nereus. In response, the sea god Poseidon, who was married to one of the Nereids, sent the sea monster Cetus to the coast of Cepheus's kingdom. Cepheus turned to the oracle of Ammon for help. The oracle told him to chain his daughter Andromeda to a rock and sacrifice her to the monster. Only in this way could the destruction off his coast be stopped. In his despair, Cepheus followed the oracle's advice. However, Andromeda was rescued just in time by the hero Perseus. Perseus then asked for Andromeda's hand in marriage. Although Andromeda had already been promised to her uncle Phineus, Cepheus agreed. In the end, a fight broke out between Perseus and Phineus at the wedding celebration. During this fight, Perseus held out the head of Medusa towards Phineus. Phineus was turned to stone on the spot.

Cepheus, Cassiopeia, Andromeda, Perseus and the monster Cetus (whale) were later placed in the sky as constellations. As punishment for her vanity, Cassiopeia circles the celestial pole on her throne for ever, at times hanging upside down.